Study On The Effect Of Slip On The Mechanical Behaviors Of Steel-concrete Composite Beams

Based on the “Performance and Analysis Research on Steel Box-Concrete ArchStructure” of the National Natural Science Foundation of China (51078373), presidedover by Pro. Zhou Zhixiang, this paper analyses the effect of slip on the mechanicalbehaviors of steel-concrete composite beams. The contents and results as below:①Based on steel-concrete interface slip differential equation, analytic solutionsof flexural stress, interface shear force and deflection of composite beams undervarious load cases are gotten. Study shows that, the effect of slip on the mechanicalbehavior of composite beams is different under various load cases and calculationsections. Combining with the actual application requirements，this paper put forwardthe simplified method of calculating the flexural stress, interface shear force anddeflection of composite beams.②The effect of residual slip on the mechanical behaviors of steel-concretecomposite beams and dead loads are analyzed, considering the studies of Hanswilleand G on the residual slip of shear connector under fatigue load. Combining with theactual application requirements，this paper put forward the simplified method ofcalculating the flexural stress, interface shear force and deflection of compositebeams.③A simplified steel-truss-concrete composite bridge mechanical model, whichignores the local flexural stress, is established based on actual applicationrequirements. This model considers shear force transferred by webs as levelconcentrated force and obfuscates the boundary condition, and the distribution law ofthe interface shear force of steel-truss-concrete composite beams is got, taking slipinto consideration.④According to the mechanical characteristics of composite beams and basedon the common finite element system, this paper puts forward a simplified finiteelement modeling method which takes interface slip into consideration and simplifiesit according to the independency of steel-concrete interface location putted forward inthis paper. Contrasted with experiment and theoretical analysis, the accuracy of thismodeling method is approved.